A number of attempts to vaccinate cancer patients with tumor cells or "tumor-associated antigenic" material obtained from the cells have yielded some positive, but largely equivocal results (1-11). A major limitation of the earlier vaccine studies was that the investigations had no immunological assay available to monitor whether they were, in fact, effectively immunizing the patients against tumor associated antigens TAA with the vaccination procedures used. The Applicants routinely use a lymphocyte-mediated lymphocyte blastogenesis assay (12) with TAA as the stimulant to determine whether the patient has had a sufficient immunological response.
Most of the published studies related to the vaccination of patients against tumors have presented the use of adjuvants such as BCG, DETOX, and viral oncolysates, alum, and complete Freund's adjuvant (1, 3, 5-9, 11) to attempt to enhance immunity against the tumor. Other studies have attempted to use high doses of lymphokine/cytokine agents including interleukin-2 IL-2 (13, 15-18) and granulocyte-macrophage colony stimulating factor GM-CSF (14) to treat patients with various types of cancer, including renal carcinoma (14-18), colorectal and lung carcinoma (16), and melanoma (14). These studies too, have demonstrated negative, or at best weakly positive, results. Varying degrees of toxicity have been associated with the use of extended high doses (one million IU or greater) of IL-2 or GM-CSF therapy, because high dose levels of these agents have been administered to the patients over extended periods of time, ranging from weeks to months. Toxic reactions have included death, renal failure, and many of the WHO Toxicity criteria such as nausea, vomiting, diarrhea, fatigue, depression, and fevers.
There are no published reports of the treatment of cancer patients with a process in which TAA is mixed with low doses (one-tenth as the Applicants do with GM-CSF or one ten-thousandth as the Applicants do with IL-2) of lymphokine/cytokine agents. There is similarly no teaching that the patients may first have undergone intense immunmodulatory chemotherapy one to three weeks prior to vaccination, or that the patient may receive a non-specific lymphocyte stimulator, such as Prozac.TM. (Hailey, Ward, McCoy, et al.: unpublished results), concurrently with the vaccine. The Applicants of the present invention have combined the use of autologous or allogeneic TAA mixed with low doses of IL-2 and GM-CSF in patients, who have or have not been treated with immunomodulatory (Haily, Ward, McCoy, et al.: unpublished results) and antineoplastic agents (e.g., cisplatin-transferrin, U.S. Pat. No. 4,590,001, Platinum bound to transferrin for use in treatment of breast cancer) within one to three weeks of vaccination and have, also, concurrently been treated with an oral non-specific lymphocyte stimulator (e.g., Prozac.TM., generically known as fluoxetine).
Tumor cell surface membrane antigen preparations obtained following hypotonic saline extraction (19) have been shown to be antigenic in inducing delayed type hypersensitivity reactions (19) in autologous cancer patients and inducing in vitro lymphocyte mediated immunity (12) using autologous or allogeneic lymphocytes from cancer patients. Thus, the results indicate that human cancers possess TAAs and the cancer-bearing host attempts to elicit a lymphocyte mediated response against the tumor. Recently, the Applicants have reported that breast cancer patients who have demonstrable lymphocyte immunity against TAA are at a very low risk of disease recurrence, suggesting that lymphocyte immunity against TAA is in some ways retarding or eliminating the growth of the tumor in those patients.
Various embodiments of the cancer vaccination process of the present invention take advantage of several factors that the inventors have found to be important in development of an immune response against foreign antigens (such as TAA). These factors include use of GM-CSF to stimulate monocytes that are vital in antigen processing and antigen presentation to lymphocytes; use of IL-2 to stimulate clonal expansion of T-lymphocytes; priming of the patient's immune system prior to vaccination with chemotherapeutic, anti-neoplastic agents, such as cis-Dichlorodiammineplatinum (II) transferrin (cisplatin-transferrin) to stimulate lymphocyte proliferation; and treatment of the patient with an oral lymphocyte proliferative stimulator such as the anti-depressant fluoxetine (Prozac.TM.). The combination of these agents and their use in the vaccination process optimizes potential development of lymphocyte immunity against tumor. The administration of the vaccine intradermally into the groin area where inguinal and mesentery lymph node drainage can occur promotes infiltration of lymphocytes and monocytes into the injection site.